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Police: Suspects swabbed Kim Jong Nam's face with toxin

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Police: Suspects swabbed Kim Jong Nam's face with toxin03:15

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Malaysian police name agent used to kill Kim Jong Nam

VX is the most toxic nerve agent

(CNN)The chemical substance used to kill Kim Jong Nam was a VX nerve agent, an internationally-banned chemical weapon that can kill within minutes, according to a preliminary report by the Chemistry Department of Malaysia.

Malaysian police said in a statement Friday that tests on Kim's eyes and face revealed the presence of the substance.

Nerve agents are the most toxic and fast-acting substance known in chemical warfare -- and VX is the most potent of all of them, according to the US Centers for Disease Control and Prevention (CDC).

Kim, the estranged half-brother of North Korean leader Kim Jong Un, died on February 13 before he was scheduled to board a flight from Kuala Lumpur to Macau.

Malaysian police claim two women wiped his face with some sort of liquid at the instruction of four North Koreans. He started to feel dizzy minutes later and died shortly after on his way to the hospital.

Despite its lethality, it's not particularly difficult to make, Francona and other experts say.

Pyongyang has had the capability to produce and use nerve agents for some time. A 2009 report from the International Crisis group estimated that the country possessed 2,500 to 5,000 tons of chemical weapons at the time, which could be delivered using artillery, rocket launchers and ballistic missiles, among other weapons.

But the blast from a delivery system like missile would likely destroy much of the VX, said Wheate. It's more meant for aerosol use in close quarters.

Pyongyang's ambassador to Malaysia, Kang Chol, accused his host country of conspiring with "hostile forces," prompting the Malaysian Prime Minister to recall his ambassador to North Korea and summon Kang.

An article published in North Korean state media Thursday fiercely rebuked Malaysia for its continued refusal to hand over Kim's body without DNA from a next of kin.

"This proves that the Malaysian side is going to politicize the transfer of the body in utter disregard of international law and morality and thus attain a sinister purpose," Thursday's article said.

Bakar, the Malaysian police inspector-general, accused North Korea of impeding the investigation.

He said Wednesday that the North Koreans had neither responded to requests to hand over the four suspects in Pyongyang, nor had they helped police find three North Koreans believed to be in Malaysia -- including an embassy employee -- who are wanted for questioning.

If the three who police think are still in Malaysia do not come forward, they will seek arrest warrants, Bakar said.

The Malaysians have requested help from Interpol, asking the international police organization to put out an alert for the four suspects believed to have trained Aishah and Huong and then returned to Pyongyang.